libv8 3.16.14.11 のインストールエラーの対応

メモ

```
Installing libv8 3.16.14.11 (was 3.16.14.3) with native extensions

Gem::Ext::BuildError: ERROR: Failed to build gem native extension.

    /Users/user/.rbenv/versions/2.1.3/bin/ruby extconf.rb
creating Makefile
Compiling v8 for x64
Using python 2.7.6
Using compiler: /usr/bin/c++ (clang version 6.1.0)
/Applications/Xcode.app/Contents/Developer/Toolchains/XcodeDefault.xctoolchain/usr/bin/libtool: file: /[Home]/vendor/bundle/ruby/2.1.0/gems/libv8-3.16.14.11/vendor/v8/out/x64.release/obj.target/preparser_lib/src/atomicops_internals_x86_gcc.o has no symbols
In file included from ../src/accessors.cc:28:
In file included from ../src/v8.h:60:
In file included from ../src/objects-inl.h:38:
In file included from ../src/elements.h:33:
In file included from ../src/heap.h:35:
In file included from ../src/incremental-marking.h:33:
In file included from ../src/mark-compact.h:32:
../src/spaces.h:896:26: error: 'this' pointer cannot be null in well-defined C++ code; comparison may be assumed to always evaluate to true [-Werror,-Wtautological-undefined-compare]
  bool exists() { return this != NULL && code_range_ != NULL; }
                         ^~~~    ~~~~
../src/spaces.h:898:9: error: 'this' pointer cannot be null in well-defined C++ code; comparison may be assumed to always evaluate to false [-Werror,-Wtautological-undefined-compare]
    if (this == NULL || code_range_ == NULL) return false;
        ^~~~    ~~~~
2 errors generated.
make[1]: *** [/[Home]/vendor/bundle/ruby/2.1.0/gems/libv8-3.16.14.11/vendor/v8/out/x64.release/obj.target/v8_base/src/accessors.o] Error 1
make: *** [x64.release] Error 2
/[Home]/vendor/bundle/ruby/2.1.0/gems/libv8-3.16.14.11/ext/libv8/location.rb:36:in `block in verify_installation!': libv8 did not install properly, expected binary v8 archive '/[Home]/vendor/bundle/ruby/2.1.0/gems/libv8-3.16.14.11/vendor/v8/out/x64.release/obj.target/tools/gyp/libv8_base.a'to exist, but it was not found (Libv8::Location::Vendor::ArchiveNotFound)
	from /[Home]/vendor/bundle/ruby/2.1.0/gems/libv8-3.16.14.11/ext/libv8/location.rb:35:in `each'
	from /[Home]/vendor/bundle/ruby/2.1.0/gems/libv8-3.16.14.11/ext/libv8/location.rb:35:in `verify_installation!'
	from /[Home]/vendor/bundle/ruby/2.1.0/gems/libv8-3.16.14.11/ext/libv8/location.rb:26:in `install!'
	from extconf.rb:7:in `<main>'
GYP_GENERATORS=make \
	build/gyp/gyp --generator-output="out" build/all.gyp \
	              -Ibuild/standalone.gypi --depth=. \
	              -Dv8_target_arch=x64 \
	              -S.x64  -Dv8_enable_backtrace=1 -Dv8_can_use_vfp2_instructions=true -Darm_fpu=vfpv2 -Dv8_can_use_vfp3_instructions=true -Darm_fpu=vfpv3 -Dwerror=''


extconf failed, exit code 1

Gem files will remain installed in /[Home]/vendor/bundle/ruby/2.1.0/gems/libv8-3.16.14.11 for inspection.
Results logged to /[Home]/vendor/bundle/ruby/2.1.0/extensions/x86_64-darwin-13/2.1.0-static/libv8-3.16.14.11/gem_make.out
An error occurred while installing libv8 (3.16.14.11), and Bundler cannot continue.
Make sure that `gem install libv8 -v '3.16.14.11'` succeeds before bundling.
```

```
$ gem install libv8 -v '3.16.14.11' -- --with-system-v8
$ bundle config build.libv8 --with-system-v8
$ bundle update
```